Table 3

Annual trends in admission biomarkers (in those admitted for pneumonia)

Initial change* per year (95% CI)Year of rate-change†Subsequent change* per year (95% CI)Direction of change‡Estimate in 2014§
Median CRP (mg/L)2.68 (0.18 to 5.17)2009−4.60 (−6.48 to −2.72)↑ ↓94
Median urea (mmol/L)0.12 (0.02 to 0.21)2004−0.01 (−0.05 to 0.03)↑ ↔7.8
Median neutrophils (×109/L)0.04 (−0.02 to 0.10)2011−0.16 (−0.28 to −0.04)↔ ↓9.7
Proportion CRP >20 mg/L−0.1 (−0.8 to 0.6)0.84
Proportion CRP >100 mg/L1.0 (−1.1 to 3.1)2009−2.3 (−3.8 to −0.7)↔ ↓0.48
Proportion urea >7 mmol/L0.5 (−0.3 to 1.3)0.58
Proportion neutrophils <2 or >7×109/L−0.1 (−0.8 to 0.6)0.75
  • Median values modelled using piecewise median regression, all other trends using piecewise linear Poisson regression.

  • *Absolute change in median values, percentage change in rate trend for proportions outside thresholds (out of those which had a test).

  • †Allowing change in trend over time if significant improvement over linear trend alone (p<0.05), with year of the change point chosen by profile likelihood8 (see Methods).

  • ‡Single arrows represent direction of change over the whole time period; paired arrows represent direction and relative size of change in the periods before and after the year when data suggested trend in rates changed (as in †).

  • §Proportion of admissions/median value, as estimated by the best-fitting model as presented in the table.

  • CRP, C reactive protein.